7 research outputs found

    Species-Area Relationships Are Controlled by Species Traits

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    The species-area relationship (SAR) is one of the most thoroughly investigated empirical relationships in ecology. Two theories have been proposed to explain SARs: classical island biogeography theory and niche theory. Classical island biogeography theory considers the processes of persistence, extinction, and colonization, whereas niche theory focuses on species requirements, such as habitat and resource use. Recent studies have called for the unification of these two theories to better explain the underlying mechanisms that generates SARs. In this context, species traits that can be related to each theory seem promising. Here we analyzed the SARs of butterfly and moth assemblages on islands differing in size and isolation. We tested whether species traits modify the SAR and the response to isolation. In addition to the expected overall effects on the area, traits related to each of the two theories increased the model fit, from 69% up to 90%. Steeper slopes have been shown to have a particularly higher sensitivity to area, which was indicated by species with restricted range (slope  = 0.82), narrow dietary niche (slope  = 0.59), low abundance (slope  = 0.52), and low reproductive potential (slope  = 0.51). We concluded that considering species traits by analyzing SARs yields considerable potential for unifying island biogeography theory and niche theory, and that the systematic and predictable effects observed when considering traits can help to guide conservation and management actions

    Time and organization studies

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    We argue that the more time is being attended to in organization studies, the more it is concealed. The time being concealed is not the time of clocks or the linear passage of past, present and future, it is not the time of temporal structures, and it is not the time of processual flow by which all substance is held as little more than a temporary arrest. In all these understandings time is treated as something available and, potentially, affirmative. Rather, it is a time that barely a few hundred years ago was considered a force always present and yet always against us. What, we ask, has happened to this time, the time beyond organization

    Pregnancy and neonatal outcomes of COVID -19: coreporting of common outcomes from PAN-COVID and AAP-SONPM registries

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    Objective Few large cohort studies have reported data on maternal, fetal, perinatal and neonatal outcomes associated with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection in pregnancy. We report the outcome of infected pregnancies from a collaboration formed early during the pandemic between the investigators of two registries, the UK and Global Pregnancy and Neonatal outcomes in COVID‐19 (PAN‐COVID) study and the American Academy of Pediatrics (AAP) Section on Neonatal–Perinatal Medicine (SONPM) National Perinatal COVID‐19 Registry. Methods This was an analysis of data from the PAN‐COVID registry (1 January to 25 July 2020), which includes pregnancies with suspected or confirmed maternal SARS‐CoV‐2 infection at any stage in pregnancy, and the AAP‐SONPM National Perinatal COVID‐19 registry (4 April to 8 August 2020), which includes pregnancies with positive maternal testing for SARS‐CoV‐2 from 14 days before delivery to 3 days after delivery. The registries collected data on maternal, fetal, perinatal and neonatal outcomes. The PAN‐COVID results are presented overall for pregnancies with suspected or confirmed SARS‐CoV‐2 infection and separately in those with confirmed infection. Results We report on 4005 pregnant women with suspected or confirmed SARS‐CoV‐2 infection (1606 from PAN‐COVID and 2399 from AAP‐SONPM). For obstetric outcomes, in PAN‐COVID overall and in those with confirmed infection in PAN‐COVID and AAP‐SONPM, respectively, maternal death occurred in 0.5%, 0.5% and 0.2% of cases, early neonatal death in 0.2%, 0.3% and 0.3% of cases and stillbirth in 0.5%, 0.6% and 0.4% of cases. Delivery was preterm (< 37 weeks' gestation) in 12.0% of all women in PAN‐COVID, in 16.1% of those women with confirmed infection in PAN‐COVID and in 15.7% of women in AAP‐SONPM. Extreme preterm delivery (< 27 weeks' gestation) occurred in 0.5% of cases in PAN‐COVID and 0.3% in AAP‐SONPM. Neonatal SARS‐CoV‐2 infection was reported in 0.9% of all deliveries in PAN‐COVID overall, in 2.0% in those with confirmed infection in PAN‐COVID and in 1.8% in AAP‐SONPM; the proportions of neonates tested were 9.5%, 20.7% and 87.2%, respectively. The rates of a small‐for‐gestational‐age (SGA) neonate were 8.2% in PAN‐COVID overall, 9.7% in those with confirmed infection and 9.6% in AAP‐SONPM. Mean gestational‐age‐adjusted birth‐weight Z‐scores were −0.03 in PAN‐COVID and −0.18 in AAP‐SONPM. Conclusions The findings from the UK and USA registries of pregnancies with SARS‐CoV‐2 infection were remarkably concordant. Preterm delivery affected a higher proportion of women than expected based on historical and contemporaneous national data. The proportions of pregnancies affected by stillbirth, a SGA infant or early neonatal death were comparable to those in historical and contemporaneous UK and USA data. Although maternal death was uncommon, the rate was higher than expected based on UK and USA population data, which is likely explained by underascertainment of women affected by milder or asymptomatic infection in pregnancy in the PAN‐COVID study, although not in the AAP‐SONPM study. The data presented support strong guidance for enhanced precautions to prevent SARS‐CoV‐2 infection in pregnancy, particularly in the context of increased risks of preterm delivery and maternal mortality, and for priority vaccination of pregnant women and women planning pregnancy. Copyright © 2021 ISUOG. Published by John Wiley & Sons Ltd
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